The present invention relates to manual control valves, and more particularly concerns such a valve in which liquid under pressure from an input port can be directed through one or the other of its ouput ports, or blocked completely.
Shipboard munitions magazines are commonly provided with sensor controlled magazine sprinkler valves which, upon sensing heat, automatically provide high pressure water to the magazine. Although primarily operated by automatic sensors, such magazine sprinkler valves are also provided with manual control valves to shut the valve after it has been turned on and to manually open and close the valve for test purposes.
The magazine sprinkler valve commonly has a pressure operated diaphragm that controls opening and closing of the valve itself. To open the magazine sprinkler valve, water under pressure is supplied to its diaphragm operating chamber. To close the magazine sprinkler valve, pressure in its operating chamber is drained through a check valve. A manual control valve, thus, can either open the magazine valve by providing pressure to its operating chamber, or it can close the magazine valve by a procedure which includes opening a check valve for draining of the operating chamber of the magazine sprinkler valve. In the ready state of the magazine sprinkler system one type of manual control valve is in a neutral position in which neither the draining check valve nor the magazine sprinkler valve is opened by the manual valve.
A manual control valve presently in use for a magazine sprinkler valve control employs a pair of lapped plates which may move relative to one another to open or close selected ones of a plurality of liquid flow passages by sliding the lapped surface of one plate over the lapped surface of another plate. Such valves are subject to leakage over a period of time because of the constant application of very high pressure. They are expensive to make, undesirably heavy, and involve a number of difficult manufacturing problems. Accordingly, it is an object of the present invention to provide a manual valve for controlling a magazine sprinkler valve which avoids or minimizes above-mentioned problems.